It seems that with TBC out all "old" professions (that is below 300 skill and in the old lands) are now dead - except mining, which brings now insane amount of cash. There was a big turmoil in tailoring when a rush for 16x bags started, but that is probably getting over now, as all aim for 18x bags. I have also made a lot of cash disenchanting items lvl50+, but I see it dying out too now.
So, I think the time of low level alt "workers" is over. They need to be able to get to Outlands to learn any useful skills.